Epilepsy Drug Can Increase Risk for Newborns, Study Says

By BENEDICT CAREY

Published: May 4, 2007

Doctors reported yesterday that expectant mothers with epilepsy who took a commonly prescribed drug to control seizures were at increased risk of having a child with mental deficits.

Toddlers who had been exposed in the womb to the drug Depakote, from Abbott Laboratories, scored seven to eight points lower on I.Q. tests at age 2 than those whose mothers had been taking other epilepsy drugs while pregnant, the study found. They were twice as likely to score in the range associated with mental retardation, according to the authors, who presented the findings at the annual meeting of the American Academy of Neurology in Boston.

Other researchers said the findings should be considered preliminary because I.Q. measures were less reliable in 2-year-olds than in older children; the study will continue, tracking children through age 6.

The report is consistent with several recent studies finding that Depakote is more likely than other so-called anticonvulsant drugs to increase the risk of mental deficits and other birth defects, like neural tube problems. An estimated 24 million American women have taken these drugs -- which include Tegretol from Novartis, Lamictal from GlaxoSmithKline and Dilantin from Parke Davis -- for an array of problems, including epilepsy, bipolar disorder and migraine headaches, according to an analysis by the Epilepsy Foundation.

''Depakote looks worse than the other drugs in all of these recent studies,'' said Dr. Kimford J. Meador, a professor of neurology at the University of Florida and the lead author of the new study. ''In all, it is compelling evidence that this drug should not be used as a first-line choice for treatment in pregnant women.''

Laureen Cassidy, a spokeswoman for Abbott, said that for many women, ''Depakote may be the only effective seizure control medication, and that decision should be made thoughtfully between physician and patient to fully evaluate the risk vs. benefit of treatment.''

The drug's label now states that Depakote ''has been associated with birth defects in children of women who have taken it while pregnant.''

Untreated seizures can endanger the life of a fetus and the expectant mother. And some 90 percent of women with epilepsy give birth to healthy, developmentally normal children even though many are taking medication, experts say.

The researchers followed 185 children through age 2, using standard I.Q. measures. The mothers in the study, while pregnant, took either Depakote, Lamictal, Tegretol or Dilantin. After controlling for the mothers' I.Q. scores, the researchers found that 2-year-olds exposed to Depakote scored significantly lower on standard intelligence measures than the others.

''It's fair to say that there has been concern about these drugs, and particularly Depakote, for the past two or three years, but we'll know the complete story about its effect on cognitive development when we look at older children,'' said Dr. Lewis Holmes, a professor of pediatrics at Harvard Medical School.